[PATCH 2/5] clk: hi3xxx: add clock support
Mike Turquette
mturquette at linaro.org
Mon May 13 15:47:03 EDT 2013
Quoting Haojian Zhuang (2013-04-19 03:49:24)
> diff --git a/drivers/clk/clk-hi3xxx.c b/drivers/clk/clk-hi3xxx.c
> new file mode 100644
> index 0000000..e93e583
> --- /dev/null
> +++ b/drivers/clk/clk-hi3xxx.c
> @@ -0,0 +1,641 @@
> +/*
> + * Hisilicon clock driver
> + *
> + * Copyright (c) 2012-2013 Hisilicon Limited.
> + * Copyright (c) 2012-2013 Linaro Limited.
> + *
> + * Author: Haojian Zhuang <haojian.zhuang at linaro.org>
> + * Xin Li <li.xin at linaro.org>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; either version 2 of the License, or
> + * (at your option) any later version.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> + * GNU General Public License for more details.
> + *
> + * You should have received a copy of the GNU General Public License along
> + * with this program; if not, write to the Free Software Foundation, Inc.,
> + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
> + *
> + */
> +
> +#include <linux/kernel.h>
> +#include <linux/clk-provider.h>
> +#include <linux/clk-private.h>
clk-private.h is deprecated and can no longer be included by any new
clock drivers. It will hopefully be removed in 3.11. Please remove it
in your next version.
> +#include <linux/clkdev.h>
> +#include <linux/delay.h>
> +#include <linux/io.h>
> +#include <linux/of.h>
> +#include <linux/of_address.h>
> +#include <linux/of_device.h>
> +#include <linux/slab.h>
> +#include <linux/clk.h>
> +
> +#define HI3620_DISABLE_OFF 0x4
> +#define HI3620_STATUS_OFF 0x8
> +
> +#define WIDTH_TO_MASK(width) ((1 << (width)) - 1)
> +
> +/*
> + * The reverse of DIV_ROUND_UP: The maximum number which
> + * divided by m is r
> + */
> +#define MULT_ROUND_UP(r, m) ((r) * (m) + (m) - 1)
> +
> +struct hi3620_periclk {
> + struct clk_hw hw;
> + void __iomem *enable; /* enable register */
> + void __iomem *reset; /* reset register */
> + u32 ebits; /* bits in enable/disable register */
> + u32 rbits; /* bits in reset/unreset register */
> + spinlock_t *lock;
> +};
> +
> +struct hi3620_muxclk {
> + struct clk_hw hw;
> + void __iomem *reg; /* mux register */
> + u8 shift;
> + u8 width;
> + u32 mbits; /* mask bits in mux register */
You need shift, width AND a mask? Normally either shift+width OR a mask
would suffice.
> + spinlock_t *lock;
> +};
> +
> +struct hi3620_divclk {
> + struct clk_hw hw;
> + void __iomem *reg; /* divider register */
> + u8 shift;
> + u8 width;
> + u32 mbits; /* mask bits in divider register */
Ditto.
> + const struct clk_div_table *table;
> + spinlock_t *lock;
> +};
> +
> +struct hs_clk {
> + void __iomem *pmctrl;
> + void __iomem *sctrl;
> + spinlock_t lock;
> +};
> +
> +static struct hs_clk hs_clk;
> +
> +static void __init hs_init_clocks(void)
> +{
> + struct device_node *node = NULL;
> +
> + if (!hs_clk.pmctrl) {
> + /* map pmctrl registers */
> + node = of_find_compatible_node(NULL, NULL, "hisilicon,pmctrl");
> + hs_clk.pmctrl = of_iomap(node, 0);
> + WARN_ON(!hs_clk.pmctrl);
> + }
> +
> + if (!hs_clk.sctrl) {
> + node = of_find_compatible_node(NULL, NULL, "hisilicon,sctrl");
> + hs_clk.sctrl = of_iomap(node, 0);
> + }
> +}
> +
> +static int hi3620_clkgate_prepare(struct clk_hw *hw)
> +{
> + struct hi3620_periclk *pclk;
> + unsigned long flags = 0;
> +
> + pclk = container_of(hw, struct hi3620_periclk, hw);
> +
> + if (pclk->lock)
> + spin_lock_irqsave(pclk->lock, flags);
> + writel_relaxed(pclk->ebits, pclk->enable + HI3620_DISABLE_OFF);
> + writel_relaxed(pclk->rbits, pclk->reset + HI3620_DISABLE_OFF);
> + readl_relaxed(pclk->reset + HI3620_STATUS_OFF);
> + if (pclk->lock)
> + spin_unlock_irqrestore(pclk->lock, flags);
> + return 0;
> +}
> +
> +static int hi3620_clkgate_enable(struct clk_hw *hw)
> +{
> + struct hi3620_periclk *pclk;
> + unsigned long flags = 0;
> +
> + pclk = container_of(hw, struct hi3620_periclk, hw);
> + if (pclk->lock)
> + spin_lock_irqsave(pclk->lock, flags);
> + writel_relaxed(pclk->ebits, pclk->enable);
> + readl_relaxed(pclk->enable + HI3620_STATUS_OFF);
> + if (pclk->lock)
> + spin_unlock_irqrestore(pclk->lock, flags);
> + return 0;
> +}
> +
> +static void hi3620_clkgate_disable(struct clk_hw *hw)
> +{
> + struct hi3620_periclk *pclk;
> + unsigned long flags = 0;
> +
> + pclk = container_of(hw, struct hi3620_periclk, hw);
> + if (pclk->lock)
> + spin_lock_irqsave(pclk->lock, flags);
> + writel_relaxed(pclk->ebits, pclk->enable + HI3620_DISABLE_OFF);
> + readl_relaxed(pclk->enable + HI3620_STATUS_OFF);
> + if (pclk->lock)
> + spin_unlock_irqrestore(pclk->lock, flags);
> +}
> +
> +static struct clk_ops hi3620_clkgate_ops = {
> + .prepare = hi3620_clkgate_prepare,
> + .enable = hi3620_clkgate_enable,
> + .disable = hi3620_clkgate_disable,
.unprepare?
> +};
> +
> +static void __init hi3620_clkgate_setup(struct device_node *np)
> +{
> + struct hi3620_periclk *pclk;
> + struct clk_init_data *init;
> + struct clk *clk;
> + const char *clk_name, *name, **parent_names;
> + u32 rdata[2], gdata[2];
> +
> + if (!hs_clk.sctrl)
> + return;
> +
> + if (of_property_read_string(np, "clock-output-names", &clk_name))
> + return;
> + if (of_property_read_u32_array(np, "hisilicon,hi3620-clkreset",
> + &rdata[0], 2))
> + return;
> + if (of_property_read_u32_array(np, "hisilicon,hi3620-clkgate",
> + &gdata[0], 2))
> + return;
> +
> + /* gate only has the fixed parent */
> + parent_names = kzalloc(sizeof(char *), GFP_KERNEL);
> + if (!parent_names)
> + return;
> + parent_names[0] = of_clk_get_parent_name(np, 0);
> +
> + pclk = kzalloc(sizeof(*pclk), GFP_KERNEL);
> + if (!pclk)
> + goto err_pclk;
> +
> + init = kzalloc(sizeof(*init), GFP_KERNEL);
> + if (!init)
> + goto err_init;
> + init->name = kstrdup(clk_name, GFP_KERNEL);
> + init->ops = &hi3620_clkgate_ops;
> + init->flags = CLK_SET_RATE_PARENT;
> + init->parent_names = parent_names;
> + init->num_parents = 1;
> +
> + pclk->reset = hs_clk.sctrl + rdata[0];
> + pclk->rbits = rdata[1];
> + pclk->enable = hs_clk.sctrl + gdata[0];
> + pclk->ebits = gdata[1];
> + pclk->lock = &hs_clk.lock;
> + pclk->hw.init = init;
> +
> + clk = clk_register(NULL, &pclk->hw);
> + if (IS_ERR(clk))
> + goto err_clk;
> + if (!of_property_read_string(np, "clock-names", &name))
> + clk_register_clkdev(clk, name, NULL);
> + of_clk_add_provider(np, of_clk_src_simple_get, clk);
> + return;
> +err_clk:
> + kfree(init);
> +err_init:
> + kfree(pclk);
> +err_pclk:
> + kfree(parent_names);
> +}
> +
> +static u8 hi3620_clk_get_parent(struct clk_hw *hw)
> +{
> + struct hi3620_muxclk *mclk;
> + u32 data;
> + unsigned long flags = 0;
> +
> + mclk = container_of(hw, struct hi3620_muxclk, hw);
> +
> + if (mclk->lock)
> + spin_lock_irqsave(mclk->lock, flags);
> +
> + data = readl_relaxed(mclk->reg) >> mclk->shift;
> + data &= WIDTH_TO_MASK(mclk->width);
> +
> + if (mclk->lock)
> + spin_unlock_irqrestore(mclk->lock, flags);
> +
> + if (data >= __clk_get_num_parents(hw->clk))
> + return -EINVAL;
> +
> + return (u8)data;
> +}
> +
> +static int hi3620_clk_set_parent(struct clk_hw *hw, u8 index)
> +{
> + struct hi3620_muxclk *mclk;
> + u32 data;
> + unsigned long flags = 0;
> +
> + mclk = container_of(hw, struct hi3620_muxclk, hw);
> +
> + if (mclk->lock)
> + spin_lock_irqsave(mclk->lock, flags);
> +
> + data = readl_relaxed(mclk->reg);
> + data &= ~(WIDTH_TO_MASK(mclk->width) << mclk->shift);
> + data |= index << mclk->shift;
> + writel_relaxed(data, mclk->reg);
> + /* set mask enable bits */
> + data |= mclk->mbits;
> + writel_relaxed(data, mclk->reg);
Is mclk->mbits equivalent to (mclk->width << mclk->shift)? If so you
can drop shift+width and use only the mask + helpers like ffs(). If
that is the case then this clock can probably use the generic clk-mux
type.
> +
> + if (mclk->lock)
> + spin_unlock_irqrestore(mclk->lock, flags);
> +
> + return 0;
> +}
> +
> +static struct clk_ops hi3620_clkmux_ops = {
> + .get_parent = hi3620_clk_get_parent,
> + .set_parent = hi3620_clk_set_parent,
> +};
> +
> +static void __init hi3620_clkmux_setup(struct device_node *np)
> +{
> + struct hi3620_muxclk *mclk;
> + struct clk_init_data *init;
> + struct clk *clk;
> + const char *clk_name, **parent_names;
> + u32 rdata[2];
> + u8 num_parents;
> + int i;
> +
> + hs_init_clocks();
> + if (!hs_clk.sctrl)
> + return;
> +
> + if (of_property_read_string(np, "clock-output-names", &clk_name))
> + return;
> + if (of_property_read_u32_array(np, "hisilicon,hi3620-clkmux",
> + &rdata[0], 2))
> + return;
> + /* get the count of items in mux */
> + for (i = 0; ; i++) {
> + /* parent's #clock-cells property is always 0 */
> + if (!of_parse_phandle(np, "clocks", i))
> + break;
> + }
> + parent_names = kzalloc(sizeof(char *) * i, GFP_KERNEL);
> + if (!parent_names)
> + return;
> +
> + for (num_parents = i, i = 0; i < num_parents; i++)
> + parent_names[i] = of_clk_get_parent_name(np, i);
> +
> + mclk = kzalloc(sizeof(*mclk), GFP_KERNEL);
> + if (!mclk)
> + goto err_mclk;
> + init = kzalloc(sizeof(*init), GFP_KERNEL);
> + if (!init)
> + goto err_init;
> + init->name = kstrdup(clk_name, GFP_KERNEL);
> + init->ops = &hi3620_clkmux_ops;
> + init->flags = CLK_SET_RATE_PARENT;
> + init->parent_names = parent_names;
> + init->num_parents = num_parents;
> +
> + mclk->reg = hs_clk.sctrl + rdata[0];
> + /* enable_mask bits are in higher 16bits */
> + mclk->mbits = rdata[1] << 16;
> + mclk->shift = ffs(rdata[1]) - 1;
> + mclk->width = fls(rdata[1]) - ffs(rdata[1]) + 1;
> + mclk->lock = &hs_clk.lock;
> + mclk->hw.init = init;
> +
> + clk = clk_register(NULL, &mclk->hw);
> + if (IS_ERR(clk))
> + goto err_clk;
> + of_clk_add_provider(np, of_clk_src_simple_get, clk);
> +
> + return;
> +err_clk:
> + kfree(init);
> +err_init:
> + kfree(mclk);
> +err_mclk:
> + kfree(parent_names);
> +}
> +
> +static void __init hs_clkgate_setup(struct device_node *np)
> +{
> + struct clk *clk;
> + const char *clk_name, **parent_names, *name;
> + unsigned long flags = 0;
> + u32 data[2];
> +
> + hs_init_clocks();
> + if (!hs_clk.sctrl)
> + return;
> + if (of_property_read_string(np, "clock-output-names", &clk_name))
> + return;
> + if (of_property_read_u32_array(np, "hisilicon,clkgate",
> + &data[0], 2))
> + return;
> + if (of_property_read_bool(np, "hisilicon,clkgate-inverted"))
> + flags = CLK_GATE_SET_TO_DISABLE;
> + /* gate only has the fixed parent */
> + parent_names = kzalloc(sizeof(char *), GFP_KERNEL);
> + if (!parent_names)
> + return;
> + parent_names[0] = of_clk_get_parent_name(np, 0);
> +
> + clk = clk_register_gate(NULL, clk_name, parent_names[0], 0,
> + hs_clk.sctrl + data[0], (u8)data[1], flags,
> + &hs_clk.lock);
> + if (IS_ERR(clk))
> + goto err;
> + if (!of_property_read_string(np, "clock-names", &name))
> + clk_register_clkdev(clk, name, NULL);
> + of_clk_add_provider(np, of_clk_src_simple_get, clk);
> + return;
> +err:
> + kfree(parent_names);
> +}
I'm working on clock bindings for the generic clock types, so hopefully
this can be replaced by those instead of using your own compatible
string to wrap around clk_register_gate.
> +
> +void __init hs_fixed_factor_setup(struct device_node *np)
> +{
> + struct clk *clk;
> + const char *clk_name, **parent_names;
> + u32 data[2];
> +
> + if (of_property_read_string(np, "clock-output-names", &clk_name))
> + return;
> + if (of_property_read_u32_array(np, "hisilicon,fixed-factor",
> + data, 2))
> + return ;
> + /* gate only has the fixed parent */
> + parent_names = kzalloc(sizeof(char *), GFP_KERNEL);
> + if (!parent_names)
> + return;
> + parent_names[0] = of_clk_get_parent_name(np, 0);
> +
> + clk = clk_register_fixed_factor(NULL, clk_name, parent_names[0], 0,
> + data[0], data[1]);
> + if (IS_ERR(clk))
> + goto err;
> + of_clk_add_provider(np, of_clk_src_simple_get, clk);
> + return;
> +err:
> + kfree(parent_names);
> +}
Ditto.
> +
> +static unsigned int hi3620_get_table_maxdiv(const struct clk_div_table *table)
> +{
> + unsigned int maxdiv = 0;
> + const struct clk_div_table *clkt;
> +
> + for (clkt = table; clkt->div; clkt++)
> + if (clkt->div > maxdiv)
> + maxdiv = clkt->div;
> + return maxdiv;
> +}
> +
> +static unsigned int hi3620_get_table_div(const struct clk_div_table *table,
> + unsigned int val)
> +{
> + const struct clk_div_table *clkt;
> +
> + for (clkt = table; clkt->div; clkt++)
> + if (clkt->val == val)
> + return clkt->div;
> + return 0;
> +}
> +
> +static unsigned int hi3620_get_table_val(const struct clk_div_table *table,
> + unsigned int div)
> +{
> + const struct clk_div_table *clkt;
> +
> + for (clkt = table; clkt->div; clkt++)
> + if (clkt->div == div)
> + return clkt->val;
> + return 0;
> +}
> +
> +static unsigned long hi3620_clkdiv_recalc_rate(struct clk_hw *hw,
> + unsigned long parent_rate)
> +{
> + struct hi3620_divclk *dclk = container_of(hw, struct hi3620_divclk, hw);
> + unsigned int div, val;
> +
> + val = readl_relaxed(dclk->reg) >> dclk->shift;
> + val &= WIDTH_TO_MASK(dclk->width);
> +
> + div = hi3620_get_table_div(dclk->table, val);
> + if (!div) {
> + pr_warning("%s: Invalid divisor for clock %s\n", __func__,
> + __clk_get_name(hw->clk));
> + return parent_rate;
> + }
> +
> + return parent_rate / div;
> +}
> +
> +static bool hi3620_is_valid_table_div(const struct clk_div_table *table,
> + unsigned int div)
> +{
> + const struct clk_div_table *clkt;
> +
> + for (clkt = table; clkt->div; clkt++)
> + if (clkt->div == div)
> + return true;
> + return false;
> +}
> +
> +static int hi3620_clkdiv_bestdiv(struct clk_hw *hw, unsigned long rate,
> + unsigned long *best_parent_rate)
> +{
> + struct hi3620_divclk *dclk = container_of(hw, struct hi3620_divclk, hw);
> + struct clk *clk_parent = __clk_get_parent(hw->clk);
> + int i, bestdiv = 0;
> + unsigned long parent_rate, best = 0, now, maxdiv;
> +
> + maxdiv = hi3620_get_table_maxdiv(dclk->table);
> +
> + if (!(__clk_get_flags(hw->clk) & CLK_SET_RATE_PARENT)) {
> + parent_rate = *best_parent_rate;
> + bestdiv = DIV_ROUND_UP(parent_rate, rate);
> + bestdiv = bestdiv == 0 ? 1 : bestdiv;
> + bestdiv = bestdiv > maxdiv ? maxdiv : bestdiv;
> + return bestdiv;
> + }
> +
> + /*
> + * The maximum divider we can use without overflowing
> + * unsigned long in rate * i below
> + */
> + maxdiv = min(ULONG_MAX / rate, maxdiv);
> +
> + for (i = 1; i <= maxdiv; i++) {
> + if (!hi3620_is_valid_table_div(dclk->table, i))
> + continue;
> + parent_rate = __clk_round_rate(clk_parent,
> + MULT_ROUND_UP(rate, i));
> + now = parent_rate / i;
> + if (now <= rate && now > best) {
> + bestdiv = i;
> + best = now;
> + *best_parent_rate = parent_rate;
> + }
> + }
> +
> + if (!bestdiv) {
> + bestdiv = hi3620_get_table_maxdiv(dclk->table);
> + *best_parent_rate = __clk_round_rate(clk_parent, 1);
> + }
> +
> + return bestdiv;
> +}
> +
> +static long hi3620_clkdiv_round_rate(struct clk_hw *hw, unsigned long rate,
> + unsigned long *prate)
> +{
> + int div;
> +
> + if (!rate)
> + rate = 1;
> + div = hi3620_clkdiv_bestdiv(hw, rate, prate);
> +
> + return *prate / div;
> +}
> +
> +static int hi3620_clkdiv_set_rate(struct clk_hw *hw, unsigned long rate,
> + unsigned long parent_rate)
> +{
> + struct hi3620_divclk *dclk = container_of(hw, struct hi3620_divclk, hw);
> + unsigned int div, value;
> + unsigned long flags = 0;
> + u32 data;
> +
> + div = parent_rate / rate;
> + value = hi3620_get_table_val(dclk->table, div);
> +
> + if (value > WIDTH_TO_MASK(dclk->width))
> + value = WIDTH_TO_MASK(dclk->width);
> +
> + if (dclk->lock)
> + spin_lock_irqsave(dclk->lock, flags);
> +
> + data = readl_relaxed(dclk->reg);
> + data &= ~(WIDTH_TO_MASK(dclk->width) << dclk->shift);
> + data |= value << dclk->shift;
> + data |= dclk->mbits;
> + writel_relaxed(data, dclk->reg);
> +
> + if (dclk->lock)
> + spin_unlock_irqrestore(dclk->lock, flags);
> +
> + return 0;
> +}
> +
> +static struct clk_ops hi3620_clkdiv_ops = {
> + .recalc_rate = hi3620_clkdiv_recalc_rate,
> + .round_rate = hi3620_clkdiv_round_rate,
> + .set_rate = hi3620_clkdiv_set_rate,
> +};
> +
> +void __init hi3620_clkdiv_setup(struct device_node *np)
> +{
> + struct clk *clk;
> + const char *clk_name, **parent_names;
> + struct clk_init_data *init;
> + struct clk_div_table *table;
> + struct hi3620_divclk *dclk;
> + unsigned int table_num;
> + int i;
> + u32 data[2];
> + const char *propname = "hisilicon,clkdiv-table";
> + const char *cellname = "#hisilicon,clkdiv-table-cells";
> + struct of_phandle_args div_table;
> +
> + hs_init_clocks();
> + if (!hs_clk.sctrl)
> + return;
> +
> + if (of_property_read_string(np, "clock-output-names", &clk_name))
> + return;
> + if (of_property_read_u32_array(np, "hisilicon,clkdiv",
> + &data[0], 2))
> + return;
> +
> + /*process the div_table*/
> + for (i = 0; ; i++) {
> + if (of_parse_phandle_with_args(np, propname, cellname,
> + i, &div_table))
> + break;
> + }
> +
> + /*table ends with <0, 0>, so plus one to table_num*/
> + table_num = i + 1;
> +
> + table = kzalloc(sizeof(struct clk_div_table) * table_num, GFP_KERNEL);
> + if (!table)
> + return ;
> +
> + for (i = 0; ; i++) {
> + if (of_parse_phandle_with_args(np, propname, cellname,
> + i, &div_table))
> + break;
> +
> + table[i].val = div_table.args[0];
> + table[i].div = div_table.args[1];
> + }
> +
> + /* gate only has the fixed parent */
> + parent_names = kzalloc(sizeof(char *), GFP_KERNEL);
> + if (!parent_names)
> + goto err_par;
> + parent_names[0] = of_clk_get_parent_name(np, 0);
> +
> + dclk = kzalloc(sizeof(*dclk), GFP_KERNEL);
> + if (!dclk)
> + goto err_dclk;
> + init = kzalloc(sizeof(*init), GFP_KERNEL);
> + if (!init)
> + goto err_init;
> + init->name = kstrdup(clk_name, GFP_KERNEL);
> + init->ops = &hi3620_clkdiv_ops;
> + init->parent_names = parent_names;
> + init->num_parents = 1;
> +
> + dclk->reg = hs_clk.sctrl + data[0];
> + dclk->shift = ffs(data[1]) - 1;
> + dclk->width = fls(data[1]) - ffs(data[1]) + 1;
> + dclk->mbits = data[1] << 16;
> + dclk->lock = &hs_clk.lock;
> + dclk->hw.init = init;
> + dclk->table = table;
> + clk = clk_register(NULL, &dclk->hw);
> + if (IS_ERR(clk))
> + goto err_clk;
> + of_clk_add_provider(np, of_clk_src_simple_get, clk);
> + return;
> +err_clk:
> + kfree(init);
> +err_init:
> + kfree(dclk);
> +err_dclk:
> + kfree(parent_names);
> +err_par:
> + kfree(table);
> +}
This looks like it was copy/pasted from the generic clk-divider type.
Is there some reason you cannot use that instead of duplicating all of
that code here?
Thanks,
Mike
> +CLK_OF_DECLARE(hi3620_mux, "hisilicon,hi3620-clk-mux", hi3620_clkmux_setup)
> +CLK_OF_DECLARE(hi3620_gate, "hisilicon,hi3620-clk-gate", hi3620_clkgate_setup)
> +CLK_OF_DECLARE(hi3620_div, "hisilicon,hi3620-clk-div", hi3620_clkdiv_setup)
> +CLK_OF_DECLARE(hs_gate, "hisilicon,clk-gate", hs_clkgate_setup)
> +CLK_OF_DECLARE(hs_fixed, "hisilicon,clk-fixed-factor", hs_fixed_factor_setup)
> --
> 1.7.10.4
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